Open PDF using JavaScript AJAX calling PHP backend

Question

I have a method, which calls the backend through AJAX, to get a blob file from MySQL database, which is retrieved by PHP.

The problem is that the PHP variables contain a string, but the AJAX call comes out empty and the PDF function does not work.

Here is the AJAX code, which is getting called.

self.showPDF = function() {
    $.ajax({
            type: 'GET',
            url: BASEURL + 'index.php/myprofile/openUserPDF/' + auth,
            contentType: 'application/json; charset=utf-8',
            dataType: 'json',
        })
        .done(function(data) {
            console.log(data);
            window.open("data:application/pdf," + escape(data));
        })
        .fail(function(jqXHR, textStatus, errorThrown) {
            alert("Could not open pdf" + errorThrown);
        })
        .always(function(data) {});
}

This is the PHP function in the backend, I am using the CodeIgniter framework.

public function openUserPDF($token) {
    if ($this->input->is_ajax_request()) {
        $userid = $this->myajax->getUserByAuth($token);
        if ($userid) {
            /* If we have an impersonated user in the session, let's use him/her. */
            if (isset($_SESSION['userImpersonated'])) {
                if ($_SESSION['userImpersonated'] > 0) {
                    $userid = $_SESSION['userImpersonated'];
                }
            }
            /* now we get the pdf of the user */
            $this->load->model('user_profile');
            $images = $this->user_profile->getUserImageForPDF($userid);
            $pdfString = $images[0]->image;
            $this->output->set_content_type('application/json');
            return $this->output->set_output(json_encode($pdfString));
        } else {
            return $this->output->set_status_header('401', 'Could not identify the user!');
        }
    } else {
        return $this->output->set_status_header('400', 'Request not understood as an Ajax request!');
    }
}

I do retrieve the blob as a string, but that's basically it, it doesn't return back to the AJAX call.

Possibilities: 1) you seem to be returning the pd f'string' as json. I am not sure that is going to work - maybe better as simple text; 2) the utf8 encoding will screw up some of the PDF data (maybe); 3) the method of creating the new window looks dodgy - afaik the window.open() command expects a URL. — Vanquished Wombat
– Vanquished Wombat, Commented Dec 29, 2016 at 12:03
@VanquishedWombat 1) so should I convert the string as simple text? 3) I looked up a lot of opening pdf commands, but could not try any of them since no data was returning so its there but not been used. — Masnad Nihit
– Masnad Nihit, Commented Dec 29, 2016 at 12:12
Sorry not an expert but I can see those few suspect issues. I would google for 'load display pdf from database ajax' and see what you find. Hopefully some working code or tutorials that you can adapt. Be sure to refine your question if needed and post the answer if you find one based on what you learn. Good luck. — Vanquished Wombat
– Vanquished Wombat, Commented Dec 29, 2016 at 12:15
Please visit this link here you can found answer. Link : stackoverflow.com/questions/1106377/…. — Bhavin
– Bhavin, Commented Dec 29, 2016 at 12:19
@Bhavin I am not downloading the file, I just want to open it in the browser. — Masnad Nihit
– Masnad Nihit, Commented Dec 29, 2016 at 12:20

public satanic void · Accepted Answer · 2019-03-04 00:10:01Z

1

It's a really, really, really, really, really bad idea to load the potentially huge contents of a PDF into memory when you could simply use file_get_contents or readfile to output it directly.

Javascript

self.showPDF = function() {
    window.open(BASE_URL + '/index.php/myprofile/openUserPDF/' + auth);
}

PHP Function

//... validation and querying ...

header('Content-type: application/pdf');
header('Content-Disposition: inline; filename="' . $filename . '"');
header('Content-Transfer-Encoding: binary');
header('Content-Length: ' . filesize($file));
header('Accept-Ranges: bytes');

readfile($pdfString);

(headers from How to render pdf file by using php; see for more information on rendering PDF files using PHP)

answered Mar 4, 2019 at 0:10

public satanic void

4604 silver badges12 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Open PDF using JavaScript AJAX calling PHP backend

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related